I use redhat in my machine, I want to install also debian in this machine,
is it possible?
if it how to do it. root / , /usr /etc are common ?

thank you for help
bela

the easiest way is to make just a / partition for both the distro's, Make a shared swap, first install debian, and then redhat or whatever, as they might have a GUI with installing a bootloader.

as far I know you shudden't make other patitions rather then / and one shared swap, as both distro's might mount the same partitions.

there's lots of info out there, so go out and read the RTFM as I mean that without any pre-justice offcourse.

Good luck.

The best thing to do is to install one version or the other, and as you do so, set up 3 or 4 disk partitions. As the other person suggested, make a common swap file. I'd recommend a swap file sized somewhere between 256 - 512 MB. Unless you're tight on memory, you won't even use that much swap space very often unless you keep a large number of processes running at the same time.

That swap file is stored on a disk partition, and it may be used by both systems. You can use a utility such as fdisk, cfdisk, GNU Parted, or the Red Hat disk druid to set up the disk partition sizes.

I would NOT recommend sharing root, /, /usr, /etc, /var, or any of the primary directories, but you can have a shared data directory. You could even call it /data and make it mountable on both systems. Don't share home directories, however, because subtle desktop differences will interfere between the two systems.

Personally, I create a disk partition, /dev/hda12 and mount it to /mnt/mozilla, then I use a soft link:

ln -sf /mnt/mozilla ~/.mozilla to create a common Web browser context between ALL of my Linux systems (and I have 8-10 of them on a single disk at any given time).

I plan to reorganize my disk again soon, and when I do, I plan to have three primary partitions available for FreeBSD, NetBSD, and OpenBSD, and around a dozen partitions available for logical Linux system partitions. Right now I have one primary partition containing a Linux system, one extended primary partition pointing to about ten logical partitions, and these have my Linux systems on them. What I have now works, but I intend to make my next change more scalable and flexible.